SERUM CONCENTRATIONS OF LUTEINIZING-HORMONE AND PROGESTERONE IN OVUM RECIPIENTS - THEIR RELATIONSHIP WITH PREGNANCY AND MISCARRIAGE

Our objective was to test the hypothesis that the association between elevated luteinizing hormone (LH) concentrations and miscarriage is me diated via an effect of LH on the maternal environment, rather than on the oocyte. The impact of maternal. age, ovarian function, previous I VF attempts, therapeutic (buserelin) and hormonal (LH, oestradiol, pro gesterone) effects occurring on the day of zygote intra-Fallopian tran sfer (ZIFT) or embryo transfer, and of oocyte or embryo numbers, wheth er they were fresh or frozen, and their mode of transfer on the occurr ence of pregnancy and miscarriage following ovum donation (n = 57) wer e investigated. The cycles were divided by outcome into non-pregnant ( n = 26), miscarriage (n = 19) and normal term pregnancy (n = 12). The circulating concentrations of LH were greater in miscarriage cycles (P = 0.046) and cycles ending in pregnancy (P = 0.04) than in non-pregna nt cycles, while the concentrations of progesterone were greater in no n-pregnant (P = 0.029) and miscarriage (P = 0.015) cycles than in cycl es ending in pregnancy. Frozen embryos were used more frequently in no n-pregnant compared to cycles ending in pregnancy (P = 0.016). Multipl e regression analysis was used to investigate which factors are associ ated with miscarriage and identified progesterone concentrations at th e time of transfer as being the only significant variable (r = 0.48, F = 8.5, P = 0.007). The same method of analysis was used to investigat e which factors are associated with the failure to conceive and identi fied previous IVF attempts (F = 5.8, P = 0.021), the presence of ovari an function (F = 5.7, P = 0.022), the use of frozen zygotes (F = 5.1, P = 0.029) and progesterone concentrations (F = 5.9, P = 0.02), with a n overall result of r = 0.59, F = 5.2 and P = 0.002. In conclusion, hi gh progesterone concentrations were associated with the failure to con ceive and miscarriage. In contrast, LH concentrations were lower in wo men who failed to conceive but similar in pregnant women who did and d id not miscarry. This suggests that the association between elevated L H concentrations and infertility is via a direct effect of LH on the o ocyte and an indirect effect, mediated by elevated progesterone concen trations, on the endometrium.